I finally finished building my sentry gun. It is the same program that POLAND_SPUD linked to in JSR's sentry gun thread. It uses a laptop and an arduino to run the code. For now the sentry uses a cheap mini electric airsoft gun, but hopefully the size and strength of the tripod will give you an idea of what is coming next

Overall I am very pleased with the way that the software works (especially considering that it is free). It was fairly easy for me to set everything up and dial it all in, and I'm not terribly experienced with programming.

The software has an option to use the creepy sound effects from Portal, but I quickly changed those to quotes from the Rambo movies

you know what I meant... if you expect ppl to pay for something it has to be substantially better than something you can get for free

In terms of hardware both turrets are the same (technically the free one is better as it uses arduino so you can add more features in the future (yeah you might even switch to step motors)). The only thing that differs them is software

For this reason I think it is wiser to choose the one that's open source as you can expect it to develop faster

jackssmirkingrevenge wrote:Nice, feet and all looking forward to seeing it with a *real* launcher mounted.

How well does it work in terms of:

- accuracy

- target identification

- target tracking

and most importantly, did you use servos or stepper motors

video?

The accuracy is pretty good, but not perfect. If you are firing towards a flat surface like a wall, the accuracy is perfect, but if you are shooting towards a wall from an angle, the aim will be off by a little bit.

Target identification works well. There are a lot of different settings you can adjust such as target size, color, etc.

Target tracking also works very well. You can set it to only track a certain color, or you can set a "safe" color. I set the color to match an airsoft bb, and the gun could track it as it rolled across the floor from about 10 feet away, which is much better than I had expected.

I used hobby servos for this project. The accuracy of the motors was not really an important issue to me when I chose them for this project because either way the motors will be more precise than the gun mounted on the turret. (Plus I felt like steppers would be a little bit harder for me to use)

I will add a video when I get a little bit more free time. I am busy right now with school and work, but I should have a video up before too long.

Well, I am in the process of building a mounting system for the turret that will make it very easy to switch out the weapons. Ideally I would like to have a variety of weapons that I could use based on where the sentry will be placed, such as a vortex bbmg for close range, a long barreled, slow ROF gun for long range, and a combination of the two for everything else.

I have spent most of my time working on the long range gun, as it will be very similar to the mid range, just optimized for greater distance. Currently I am working on a blow forward style very similar to the one JSR made a while back. I'm a big fan of that design. After I finish the long range gun, I will probably just use the same basic idea for the mid range, except with a higher ROF and a shorter barrel.

The main issue that I am having with all of these designs is the fact that they require compressed air, which is not nearly as portable as the battery pack that the mini electric gun uses.

My other thought with using a modular type mount is that I could even mount some of my airsoft guns to the turret, like gas blowback pistols, AEG's, or even a gas sniper. It would be quick and easy to switch them out even in the middle of a battle.